1. Field of the Invention
This invention relates to a method and apparatus for encapsulating a ring-shaped member, such as a wound coil of wire, with a casing having a relatively constant thickness and rounded edges, and wherein the encapsulated ring-shaped member is stress-relieved.
1. Description of Prior Art
Conventional methods have been used to encapsulate ring-shaped members, such as wound coils of wire. For example, wound coils have been dipped in an epoxy material or an enamel material. The dipping process results in a coated or encapsulated wound coil. However, the wall thickness of the coating can significantly differ because of manufacturing inconsistencies associated with different variables, such as materials and gravity effects.
In other conventional methods, a wound coil is encased by positioning the wound coil within a prefabricated casing or housing having two or more pieces. The multiple casing or housing pieces are then welded, adhered or otherwise sealed or mechanically connected with respect to each other.
The different conventional methods for encapsulating a ring-shaped member produce casings with variable wall thicknesses and casing that have exposed sharp edges. Encapsulated wound coils are used to manufacturer toroidal coils, wherein a wire is wound in a toroidal fashion about the casing of an encapsulated wound coil. Inconsistent casing thicknesses can result in inaccurate toroidal windings. Because tension is applied to a toroidal wire during a winding process, a sharp casing edge can sever and thus break the toroidal wire during the winding process.
There is an apparent need for a method and apparatus for encapsulating a wound coil, wherein the casing has a relatively constant thickness with no exposed sharp edges, to provide a base for winding a consistent and accurate toroidal coil, particularly without breaking the toroidal wire. Also, there is a need to provide a method and apparatus for mass producing at relatively high production speeds an encapsulated ring-shaped member, such as a wound coil.